The invention relates to a process for ventilating a passenger compartment of a motor vehicle which has a ventilating device and has at least one roof opening, which can be opened and closed by means of an actuating device.
U. S. Pat. No. 4,556,835 describes movable parts for an actuating device for the selective closing or exposing of openings, particularly for sliding roofs and sliding lifting roofs of motor vehicles. The configuration of the actuating device described therein is such that only the actuating member itself has to be brought into a position corresponding to the set point position of the movable part. A control circuit automatically causes the control unit to bring the movable part into the required set position, and bring it to rest there, thus, eliminating the need for the driver to monitor the movable part itself. The configuration described in the above reference comprises an actuating device, including a set point indicator by which a certain position of the movable part can be pre-selected, and also provides that there is a control circuit which compares the actual position of the movable part with the set position, and drives the movable part up to the point where it equals the set position.
Furthermore, a motor vehicle usually has a ventilating device by which fresh air or climatized air can be introduced into the vehicle passenger compartment. In a motor vehicle which has a device for actuating a sliding roof or a sliding-lifting roof or the like, the roof opening is at least partially opened or closed independently of the other devices of the motor vehicle. In like manner, the customary ventilating device in a vehicle is actuated independently of a vehicle sliding roof, i.e. it is open, partially open, or closed.
Accordingly, it has been found, for instance, that the effect of the ventilating device is not always favorable with regard to the degree of efficiency obtained. This can be attributed to the fact that, for instance, problems can arise in connection with a choked-off air exhaust from the motor vehicle when the roof opening is closed and the ventilating device is open.